0.37 16 x 1 in. 0.31 Head Header Bolt Motor State Distributing has set the pace for highperformance automotive components for racing, street, and offroad use. We offer wide range of quality auto accessories. Features. Durable and reliable construction. Lightweight and easy to use. Pack of 16Specifications. Size 0.37 16 x 1 in.. Head Size 0.31